Sandpaper holder



Juy 16, 1946. R. H. sMlTH l SANDPAPER HOLDER Fild July 1, 1944 2 Sheets-Sheet 1 I NVENTOR SMITH 2,404,105

SANDPAPER HOLDER 2 Sheets-Sheet 2 Filed July 1, 1944 Fuy E6; 1946.

INVENTOR ATTORNEY Patented July 16, 1946 UNITED STATES: PATENT OFFICE SANDPAPER :HOLDER Rohley Hume Smith, The Dalles, Oreg.

Application Julyl, 1944, Serial N0. 543,125

1 claim. 1

'Ihe object of this invention is to supply a satisfactory tool for holding sandpaper securely while being used to roughen or smooth surfaces, whatever the contour, that require recoating with enamel, varnish, paint or similar material.

A further object of this invention is the provision of a tool which does not overreach the exible limitation of sandpaper by a thoughtless disregard of disrupting the cohesive strength in the union of grit, glue and paper incident to a too sharp a curve at the holders or to the use of serrated clamps. Y

A further object of this invention is to obtain greater economy in the use of sheet abrasive.

Other advantages will be apparent from the specification and drawings.

In the drawings: I i

Figure 1 is a perspective viewof my new and improved sandpaper holder.

Figure 2 is a perspective View of one of an identical pair of sandpaper locking devices.

Figure 3 is a perspective-view of one of several identical felt pads. Y Y

Figure 4 is a perspective view of one of several identical metal elements for helping to hold the felt pads in alignment.

Figure 5 is a perspective view of two main frame elements that, considered as a pair, or separately, are duplicated.

vFigure -6 is a sectional view of the tool take on line 6 6 of Figure 7,

Figure 7 is a, plan view of the tool, partially broken away for convenience of illustration.

Figure 8 is a sectional view of the tool, taken on line 8 8 of Figure '7.

With regard to the drawings, as identified, they are to a certain extent freehand illustrations of the shapes, sizes and positions of the standardized or implement parts of the invention, hence saiddrawings are not altogether precise, nor intended to be any other than approximationsa principle, I would have it understood, suggestive -of anticipated modifications within reason, of

course, and in accord with the scope and spirit of my invention.

t (section 2), onev clearly illustrated in Figure 2,:

both indicated as emplaoedin Figures 6, 7 and 8, and the sandpaper matrix (section l) minus a numerical designation in the drawings but containing-allthe remaining parts and elements for-- completing the tool, said sections described in detail hereinafter. k

Section 1, the sandpaper matrix, in a general sense is composed of Va dual series of` light sheet .metal units and resilient fabricunits strung in alternation on a pair of rods 8 in aY manner to be known as loose-fitting and tight-tting, respectively. The metal units as shown Yin vFigure '7, designated numerically as I, 2 (implied in the break-away but shown in Figure 5), L5 and ,6, while the fabric units are designated as 1V and 26, said dual units either metal or fabric easily recognized, independent of numerical notationsVby a mere glance at the drawings shown as Figures 1, 3, 4, 5, 6, 7 and 8. l

Moreover, section 1, the sandpaper matrix,'in a specific sense, has its various parts and elements described in detail now, eachin the order of its assemblage, starting with the metal strip 5, Figure 1, known as a splint per se and shown as isolated in Figure 4 and meant to be placed (in the assemblage) in close contactwith a fabric 1 as inFigure 3, said fabric known as av felt pad (being composed of twofold fourply pieces of felt) sewed 1A for holding the folds together while punching the holes 9 and creating the curves at each end, said curves within .thelimit (by design) of the flexibility of the sandpaper for taking the said curves Without a disruption of grit, glue and paper, said splint per se helping to keep the felt pad in alignment, being aided Vin that function by having its lower line coincident,

or practically so, with the broken line 1A, meaning close to, not upon the folds of the felt pad; (glance at Figure 8 at the multiple folds of as many felt pads for easy comprehension of the reference to folds) And now follows in the assemblage a fabric unit 26 consisting of a onefold twoply piece of felt (not exactly a preferable material because of a war priority) known as a guardrail used as a protective appurtenance for avoiding the creation of a blemish from anabrupt inoautious approach to surfaces that must not be scratched by sandpaper, citing chrome `strips on I combined with other elements, each of said main frame elements I and 2 having along its rectilinear top line a ninety degree crimp with a depth the thickness of a felt pad, Figure 3, whereas, the said element I, Figure 5, is provided with a pair of sawtooth crimps on its lower line, one at each end, by means of which, in combination with its own top line crimp and that of its fellow element, the elements I and 2 as shown in Figure 8 are held apart and parallel preventing thereby a possible pinching of the metal inember I2 (see Figure 2) shown in Figures 7 and 48 as inserted between the top line crimps of the said main frame elements. In such a position, the metal member I2 must have a freedom of movement as the need requires and gets it as a shuttle in a pair of perfect races.

Let it be noted now that the main frame elements I and 2, Figure 8, are apparent splints, one on each side of afelt pad, each of said elements to be known as a resolved splint in the appended claim, as distinguished from a splint per se, Figure 4, so named, first, because its lower iline has the form and the position, hence the function, .of a splint per se. and because, second, the said main frame elements have other functions, vas complements to counterparts, noted hereinafter in the novel act of combining instantly the three sections of the tool into an integrated whole. So far ve units have .been strung on Vthe rods 8 and described. On the opposite ,side of the tool are duplicate units as shown in Figure 7 or 8 and in reversemaking the original group and the duplicated group of units represent so called rights and lefts, as it were.

Between said groups of units, as shown in the plan view of the tool, Figure 7, Aare by .actual count ten fabric units 1 ,and nine metal units 5. The central metal unit 6 Yas shown in Figure. 6 clearly illustrated as a ratchet plane 21 with its notches 28 and manifestly a complement, in duplicate, to its counterpart readily recognized Vasa pawl, completes the assemblage and, like the main frame elements, is to be known .as a resolved splint also. But notice further in this section 1 .that the top Ylines of the two opposite and vduplicate main frame elements 2 are in an imaginary plane vabove the common level of the feltpads and the splints per se, allowance being made thereby for the yneeded space required by the bolthead 2l and its 1ock22 as indicated in Figure 8, said bolthead locking device placed directly beneath the so-called shuttle member I2 inserted between the top line crimps of the two opposite pairs of main frame elements I and 2, shown likewise in Figure 8 and later amplified.

SectionZ, an .identical pair of sandpaper locking devices, shall vbe `called a square-j awed mouth II with pendent lips I4 and I5, referring to one of the pair indicated in Figure 2. The lower jaw I2 is stationary; the upper jaw I3, movable. As illustrated, the mouth II is agape and held thus by a full lengthmolecular spring pivoted at I3A. accounting for the upward movement of jaw I3, while the use of the nuts 23 on the bolts 2B eX- hibits the force for a downward movement of the jaw which in moving describes an arc unhampered by the threads of the vertical bolts 29 inasmuch as the holes in said upper jaw through which the bolts 20 are thrust are large enough to permit the freedom of movement along the predetermined arc with no obstructive entanglef ment of Vthe light sheet metal jaw in the troughs of the threads. The lips I4 and I5 are the sandpaper I6 holders as shown in vFigure 6, said holders having a twofold gripping value, one oi which ascribed to a frictional contact of the sandpaper I6 with the lips III and I5 when the nuts 23 are tightened (always by the fingers, not a wrench, as in the case of all other nuts in the tool), the other gripping value ascribed to the curve of the clamps. But notice that the lips are pendent, meaning that they swing beyond the ends of the main frame elements I and 2. So, .inasmuch as the jaws I2 and I3 straddle the upper opposite main frame elements I as shown in Figure '7, a thin sheet of sandpaper with its fine-bolted grit cannot be clamped securely, hence the need of the pendent lip and a secondary molecular spring in the upper jaw I3, said spring pivoted along the line of contact of the lower edge of parallelepiped gure (in the upper jaw) with the topmost main frame elements, a provision that solves the problem of clamping thin sandpaper. The lower jaw I2 described already in section 1 asa shuttle (though for a moment only) provided with proper races which are the crimps of the paired main frame elements I and 2 as shown in Figure 8, and denoted as a counterpart to a complement in section l, has a molecular spring pivoted at the lines where the flanks ofthe jaw break away from the races as shown in Figure '7, said molecular spring determines the strength in the snap of the pawl into a ratchet notch 28 as shown in Figure 6 for holding section 1 to section 2, said flanks of the jaw when thernuts It are tightened on the rods 8 as shown to be done as yet in Figure 8, act as stabilizers of the tool when brought in close contact with the sides of the outer opposite main frame elements I.

Underneath the lower jaw I2 ofthe mouth II as shown in Figure 8 is a bolthead. locking device, one of an identical four in the tool, said locking device consisting of a rectangular strip 2I of light sheet metal bent to slip into the groove 22 of the bolthead for holding it fastwhen the nut 23 of the bolt 2B is used. The hole in the metal strip 2I has the diameter of the bolt 29, said strip with the bolt thrust through it is held close up to the jaw I2 through which the bolt protrudes in a tight t and extends thro-ugh the upper jaw I3 vwith the hole in it designedly loosetting, thence the bolt 29 is passed through a pearshaped hole 25, one of four and identical, in the shell-like handhold 24 indicated in the Figures 1 and 8, and shown nally with its end protruding for the reason that the said boltend, in company with three others of its kind, is to be known as a bitching post in the nature of a complement to a counterpart when section 2 is hitched to section 3.

Section 3, the handhold 24, with its position illustrated in Figures 1, 6 and 8, consisting of a rectangular piece of light sheet metal in the shape of a shell the whole of which forming a molecular Yspring pivoted on the boltends 20 next to the nuts 23 by by means of four pearshaped ,holes created from overlapping circles, the smaller ends of such composite holes being semicircles having the diameter of the bolts 20, said molecular spring in all the illustrations is active, not inert, and therefore the force for holding the four semicircles jam against the troughs in the threads adjacent to the nuts 23 as illustrated and hereinafter described more fully when the molecular spring is inert at the moment for attaching the section 3 to section 2.

As `to joining (or disjoining) the three'sections of the tool into an integrated whole almost in a ash, note Figure 7 in which the pair of sandpaper locking devices II, known as section 2, are attached to the sandpaper matrix known as section 1. In separating section 2 from section 1, I loosen the nuts III on the rods 8 the least bit, rst, an act for disengaging slightly the hold the outer main frame elements I at the opposite sides of the tool has on the flanks of the lower jaw l2 Figure 2 more clearly shown; second, I lift the pawl I3A, Figure 2, or shown more clearly in Figure 6 as occupying a notch 28 in the ratchet plane 21, and in the lift overcoming the force of a molecular spring located in the jaw I2 of the mouth II then, third, push the sandpaper locking device known as a smouth outward from the tool (or section 1) and off. In a reverse procedure the section 2 is back again, locked securely to section 1.

In Figure 1 the handhold 24 known as section three is fastened to the pair of sandpaper locking devices Il known as section 2 which, in turn, is attached to the sandpaper matrix known as section 1. To remove the handheld 24 from the sandpaper locking devices II, take hold of the shell at its sides, exert a lateral pressure on the shell until the larger ends of the pear-shaped holes 25 swap places with the smaller semicircular ends which the molecular spring held tight in the troughs of the threaded boltends and jam against the nuts 23. Having brought the shell into that position, lift it off, whereupon the molecular spring is inert. To replace the handhold, then, reverse the procedure; that is, exert a lateral pressure on the shell, having brought it into a position in which the composite holes 25 are above the boltends 20, until the larger ends of the composite holes 25 are directly above, or nearly so, the boltends 20, and while in that new position above the metal shell down and jam against the nuts 23 as in Figure 8. Now release the molecular spring. Thereupon, the metal shell takes hold of section 2 in a semicircular grasp and holds fast to its assigned troughs.

In loading the tool with sandpaper I6, ilrst remove the handhold to get at the nuts 23. Figure 6 indicates that the sandpaper is loaded already, but imagine that the lips I4 and I5, between which the sandpaper is shown, are open.

Then above the one end of sandpaper I6 between the lips I4 and I5 up against the bolts 20 which are called endstops, thereupon tighten the nuts 23 slightly, relying largely on a mere frictional engagement of the'- sandpaper with the lips for a momentary clasp-a tenuous holdand after that procedure the sandpaper is brought to the second clasp at the opposite end of the tool, having kept the lateral edges of the paper parallel to the so-called guardrail of felt while placing the unattached end of the paper between the second pair of lips I4 and I5 (endstops not of use here) and making the paper fast by tightening the nuts 23, thereafter loosening the nuts at the opposite end of the tool and taking up the slack in the paper for a nal fastening, using fingers.

Take note that the lips I4 and I5 are curved and represent arcs that are a prolongation cf the original arcs shown at the ends of feltpads over which the sandpaper is passed, in being loaded and used, with no sign of having reached, disastrously, beyond the limitation of flexibility.

In using the tool bear in mind that the sandpaper has a background of several folds of felt, said folds resembling nodes and loops, said loops equivalent to waves the crests of which bring manifold lines of sandpaper to bear on the surface to be abraded, whether the tool in use moves in transverse, oblique or horizontal directio-ns. The idea is to multiply the cutting lines of the sandpaper indenitely, consuming its entire value available, except the remnants in the clamps, said remnants being used later in the miniature tools each known as an individual sandpaper locking device, Figure 2. In feather edging use the curved ends of the tool as a means of avoiding too large a range of feather edging with a consequent waste 0f abrasive material. In using the guardrail of felt as a protective appurtenance for saving strips of chrome ornamentation, for example, from incautious scratches, bring the lateral side of the tool close to the ornament, press down on the tool and slide it, tilted, close up to the ornament. Such a maneuver forces the guardrail under the sandpaper at its edge, permitting necessary abrading close to the stripand no harm done from scratching.

Having given a detailed description of my invention, supplemented by drawings, what I claim A device of the class described comprising a body member having curved ends and being adapted to support a strip of abrasive material, said body member consisting of a plurality of layers of felt and narrow metal reinforcing strips interleaved between the felt layers adapted to reinforce and stien the felt layers, narrow side members on each longitudinal side having right angle beads formed at the tops thereof and extending partly across the top of the body member, spring jaw member at each end of the body member having ange members extending beneath the beads on the side members and clamped to the 4body member thereby, means engaging the jaw members to force the gripping of the jaw members together, a pair of felt guard rails along each longitudinal side of the body member and extending beyond the abrasive supporting face thereof, bolt members adjacent each end of the body member passing through the side rails and body securely clamping the rails and body members together and a strip of abrasive material having each end clamped in a jaw member and being snugly supported by the body member. f

ROBLEY HUME SMITH. 

